Gift ideas for SO, need help

I hate to resort to asking strangers on the Internet but his birthday is only two days away and I'm starting to panic because I haven't come up with anything. If anyone could leave any suggestions it would be highly appreciated.

About him:

• massive nerd who loves comics/superheroes

• plays trombone

• loves almost anything nerdy

• very socially awkward (by his own admission)

• sarcastic asshole who is also very lovable

I'm so bad at describing people wow I'm sorry. Thanks for your help!